I guess you mean:
(3-3i)/4i
or
(3/4)(1/i -i/i)
so the real questions are:
What is 1/i and what is i/i
first one:
1/i * i/i = i/-1 = -i
second one:
i/i = 1
so we have:
(3/4)(-i - 1)
or
-3/4 - (3/4)i
so I agree except for the trivial point that that standard form is a + b i not b i + a